Merge branch 'next-smack' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull smack updates from James Morris:
 "Bug fixes for IPv6 handling and other issues and two memory use
  improvements."

* 'next-smack' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  Smack: Fix kbuild reported build error
  smack: Check address length before reading address family
  Smack: Fix IPv6 handling of 0 secmark
  Smack: Create smack_rule cache to optimize memory usage
  smack: removal of global rule list

security/smack/smack.h

@@ -348,6 +348,7 @@ extern struct list_head smack_onlycap_list;
 
 #define SMACK_HASH_SLOTS 16
 extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS];
+extern struct kmem_cache *smack_rule_cache;
 
 static inline struct task_smack *smack_cred(const struct cred *cred)
 {

security/smack/smack_lsm.c

@@ -59,6 +59,7 @@ DEFINE_MUTEX(smack_ipv6_lock);
 static LIST_HEAD(smk_ipv6_port_list);
 #endif
 static struct kmem_cache *smack_inode_cache;
+struct kmem_cache *smack_rule_cache;
 int smack_enabled;
 
 #define A(s) {"smack"#s, sizeof("smack"#s) - 1, Opt_##s}
@@ -354,7 +355,7 @@ static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
 	int rc = 0;
 
 	list_for_each_entry_rcu(orp, ohead, list) {
-		nrp = kzalloc(sizeof(struct smack_rule), gfp);
+		nrp = kmem_cache_zalloc(smack_rule_cache, gfp);
 		if (nrp == NULL) {
 			rc = -ENOMEM;
 			break;
@@ -1931,7 +1932,7 @@ static void smack_cred_free(struct cred *cred)
 	list_for_each_safe(l, n, &tsp->smk_rules) {
 		rp = list_entry(l, struct smack_rule, list);
 		list_del(&rp->list);
-		kfree(rp);
+		kmem_cache_free(smack_rule_cache, rp);
 	}
 }
 
@@ -2805,13 +2806,17 @@ static int smack_socket_socketpair(struct socket *socka,
  *
  * Records the label bound to a port.
  *
- * Returns 0
+ * Returns 0 on success, and error code otherwise
  */
 static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
 				int addrlen)
 {
-	if (sock->sk != NULL && sock->sk->sk_family == PF_INET6)
+	if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) {
+		if (addrlen < SIN6_LEN_RFC2133 ||
+		    address->sa_family != AF_INET6)
+			return -EINVAL;
 		smk_ipv6_port_label(sock, address);
+	}
 	return 0;
 }
 #endif /* SMACK_IPV6_PORT_LABELING */
@@ -2847,12 +2852,13 @@ static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
 
 	switch (sock->sk->sk_family) {
 	case PF_INET:
-		if (addrlen < sizeof(struct sockaddr_in))
+		if (addrlen < sizeof(struct sockaddr_in) ||
+		    sap->sa_family != AF_INET)
 			return -EINVAL;
 		rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
 		break;
 	case PF_INET6:
-		if (addrlen < sizeof(struct sockaddr_in6))
+		if (addrlen < SIN6_LEN_RFC2133 || sap->sa_family != AF_INET6)
 			return -EINVAL;
 #ifdef SMACK_IPV6_SECMARK_LABELING
 		rsp = smack_ipv6host_label(sip);
@@ -3682,9 +3688,16 @@ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
 
 	switch (sock->sk->sk_family) {
 	case AF_INET:
+		if (msg->msg_namelen < sizeof(struct sockaddr_in) ||
+		    sip->sin_family != AF_INET)
+			return -EINVAL;
 		rc = smack_netlabel_send(sock->sk, sip);
 		break;
+#if IS_ENABLED(CONFIG_IPV6)
 	case AF_INET6:
+		if (msg->msg_namelen < SIN6_LEN_RFC2133 ||
+		    sap->sin6_family != AF_INET6)
+			return -EINVAL;
 #ifdef SMACK_IPV6_SECMARK_LABELING
 		rsp = smack_ipv6host_label(sap);
 		if (rsp != NULL)
@@ -3694,6 +3707,7 @@ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
 #ifdef SMACK_IPV6_PORT_LABELING
 		rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
 #endif
+#endif /* IS_ENABLED(CONFIG_IPV6) */
 		break;
 	}
 	return rc;
@@ -3906,6 +3920,8 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 #ifdef SMACK_IPV6_SECMARK_LABELING
 		if (skb && skb->secmark != 0)
 			skp = smack_from_secid(skb->secmark);
+		else if (smk_ipv6_localhost(&sadd))
+			break;
 		else
 			skp = smack_ipv6host_label(&sadd);
 		if (skp == NULL)
@@ -4758,6 +4774,12 @@ static __init int smack_init(void)
 	if (!smack_inode_cache)
 		return -ENOMEM;
 
+	smack_rule_cache = KMEM_CACHE(smack_rule, 0);
+	if (!smack_rule_cache) {
+		kmem_cache_destroy(smack_inode_cache);
+		return -ENOMEM;
+	}
+
 	/*
 	 * Set the security state for the initial task.
 	 */

security/smack/smackfs.c

@@ -67,7 +67,6 @@ enum smk_inos {
 /*
  * List locks
  */
-static DEFINE_MUTEX(smack_master_list_lock);
 static DEFINE_MUTEX(smack_cipso_lock);
 static DEFINE_MUTEX(smack_ambient_lock);
 static DEFINE_MUTEX(smk_net4addr_lock);
@@ -134,15 +133,7 @@ LIST_HEAD(smk_net6addr_list);
 
 /*
  * Rule lists are maintained for each label.
- * This master list is just for reading /smack/load and /smack/load2.
  */
-struct smack_master_list {
-	struct list_head	list;
-	struct smack_rule	*smk_rule;
-};
-
-static LIST_HEAD(smack_rule_list);
-
 struct smack_parsed_rule {
 	struct smack_known	*smk_subject;
 	struct smack_known	*smk_object;
@@ -211,7 +202,6 @@ static void smk_netlabel_audit_set(struct netlbl_audit *nap)
  * @srp: the rule to add or replace
  * @rule_list: the list of rules
  * @rule_lock: the rule list lock
- * @global: if non-zero, indicates a global rule
  *
  * Looks through the current subject/object/access list for
  * the subject/object pair and replaces the access that was
@@ -223,10 +213,9 @@ static void smk_netlabel_audit_set(struct netlbl_audit *nap)
  */
 static int smk_set_access(struct smack_parsed_rule *srp,
 				struct list_head *rule_list,
-				struct mutex *rule_lock, int global)
+				struct mutex *rule_lock)
 {
 	struct smack_rule *sp;
-	struct smack_master_list *smlp;
 	int found = 0;
 	int rc = 0;
 
@@ -247,7 +236,7 @@ static int smk_set_access(struct smack_parsed_rule *srp,
 	}
 
 	if (found == 0) {
-		sp = kzalloc(sizeof(*sp), GFP_KERNEL);
+		sp = kmem_cache_zalloc(smack_rule_cache, GFP_KERNEL);
 		if (sp == NULL) {
 			rc = -ENOMEM;
 			goto out;
@@ -258,22 +247,6 @@ static int smk_set_access(struct smack_parsed_rule *srp,
 		sp->smk_access = srp->smk_access1 & ~srp->smk_access2;
 
 		list_add_rcu(&sp->list, rule_list);
-		/*
-		 * If this is a global as opposed to self and a new rule
-		 * it needs to get added for reporting.
-		 */
-		if (global) {
-			mutex_unlock(rule_lock);
-			smlp = kzalloc(sizeof(*smlp), GFP_KERNEL);
-			if (smlp != NULL) {
-				smlp->smk_rule = sp;
-				mutex_lock(&smack_master_list_lock);
-				list_add_rcu(&smlp->list, &smack_rule_list);
-				mutex_unlock(&smack_master_list_lock);
-			} else
-				rc = -ENOMEM;
-			return rc;
-		}
 	}
 
 out:
@@ -540,9 +513,9 @@ static ssize_t smk_write_rules_list(struct file *file, const char __user *buf,
 
 		if (rule_list == NULL)
 			rc = smk_set_access(&rule, &rule.smk_subject->smk_rules,
-				&rule.smk_subject->smk_rules_lock, 1);
+				&rule.smk_subject->smk_rules_lock);
 		else
-			rc = smk_set_access(&rule, rule_list, rule_lock, 0);
+			rc = smk_set_access(&rule, rule_list, rule_lock);
 
 		if (rc)
 			goto out;
@@ -636,21 +609,23 @@ static void smk_rule_show(struct seq_file *s, struct smack_rule *srp, int max)
 
 static void *load2_seq_start(struct seq_file *s, loff_t *pos)
 {
-	return smk_seq_start(s, pos, &smack_rule_list);
+	return smk_seq_start(s, pos, &smack_known_list);
 }
 
 static void *load2_seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
-	return smk_seq_next(s, v, pos, &smack_rule_list);
+	return smk_seq_next(s, v, pos, &smack_known_list);
 }
 
 static int load_seq_show(struct seq_file *s, void *v)
 {
 	struct list_head *list = v;
-	struct smack_master_list *smlp =
-		list_entry_rcu(list, struct smack_master_list, list);
+	struct smack_rule *srp;
+	struct smack_known *skp =
+		list_entry_rcu(list, struct smack_known, list);
 
-	smk_rule_show(s, smlp->smk_rule, SMK_LABELLEN);
+	list_for_each_entry_rcu(srp, &skp->smk_rules, list)
+		smk_rule_show(s, srp, SMK_LABELLEN);
 
 	return 0;
 }
@@ -2352,10 +2327,12 @@ static const struct file_operations smk_access_ops = {
 static int load2_seq_show(struct seq_file *s, void *v)
 {
 	struct list_head *list = v;
-	struct smack_master_list *smlp =
-		list_entry_rcu(list, struct smack_master_list, list);
+	struct smack_rule *srp;
+	struct smack_known *skp =
+		list_entry_rcu(list, struct smack_known, list);
 
-	smk_rule_show(s, smlp->smk_rule, SMK_LONGLABEL);
+	list_for_each_entry_rcu(srp, &skp->smk_rules, list)
+		smk_rule_show(s, srp, SMK_LONGLABEL);
 
 	return 0;
 }